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1.
Ecotoxicol Environ Saf ; 208: 111412, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33039872

RESUMO

Cadmium (Cd) is a severely toxic and carcinogenic heavy metal. Cigarette smoking is one of the major source of Cd exposure in humans. Nicotiana tabacum is primarily a leaf Cd accumulator, while Nicotiana rustica is a root Cd accumulator among Nicotiana species. However, little is known about the mechanisms of differential Cd translocation and accumulation in Nicotiana. To find the key factors, Cd concentration, Cd chemical forms, and transcriptome analysis were comparatively studied between N. tabacum and N. rustica under control or 10 µM Cd stress. The leaf/root Cd concentration ratio of N. tabacum was 2.26 and that of N. rustica was 0.14. The Cd concentration in xylem sap of N. tabacum was significantly higher than that of N. rustica. The root of N. tabacum had obviously higher proportion of ethanol extractable Cd (40%) and water extractable Cd (16%) than those of N. rustica (16% and 6%). Meanwhile the proportion of sodium chloride extracted Cd in N. rustica (71%) was significantly higher than that in N. tabacum (30%). A total of 30710 genes expressed differentially between the two species at control, while this value was 30,294 under Cd stress, among which 27,018 were collective genes, manifesting the two species existed enormous genetic differences. KEGG pathway analysis showed the phenylpropanoid biosynthesis pathway was overrepresented between the two species under Cd stress. Several genes associated with pectin methylesterase, suberin and lignin synthesis, and heavy metal transport were discovered to be differential expressed genes between two species. The results suggested that the higher accumulation of Cd in the leaf of N. tabacum depends on a comprehensive coordination of Cd transport, including less cell wall binding, weaker impediment by the Casparian strip, and efficient xylem loading.


Assuntos
Cádmio/toxicidade , Nicotiana/fisiologia , Transcriptoma , Parede Celular/metabolismo , Perfilação da Expressão Gênica , Humanos , Metais Pesados/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Nicotiana/metabolismo , Xilema/metabolismo
2.
Front Plant Sci ; 11: 556, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32477386

RESUMO

Chilling is a major abiotic factor limiting the growth, development, and productivity of plants. ß-aminobutyric acid (BABA), a new environmentally friendly agent, is widely used to induce plant resistance to biotic and abiotic stress. Calcium, as a signaling substance, participates in various physiological activities in cells and plays a positive role in plant defense against cold conditions. In this study, we used tobacco as a model plant to determine whether BABA could alleviate chilling stress and further to explore the relationship between BABA and Ca2+. The results showed that 0.2 mM BABA significantly reduced the damage to tobacco seedlings from chilling stress, as evidenced by an increase in photosynthetic pigments, the maintenance of cell structure, and upregulated expression of NtLDC1, NtERD10B, and NtERD10D. Furthermore, 0.2 mM BABA combined with 10 mM Ca2+ increased the fresh and dry weights of both roots and shoots markedly. Compared to that with single BABA treatment, adding Ca2+ reduced cold injury to the plant cell membrane, decreased ROS production, and increased antioxidant enzyme activities and antioxidant contents. The combination of BABA and Ca2+ also improved abscisic acid and auxin contents in tobacco seedlings under chilling stress, whereas ethylene glycol-bis (ß-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) reversed the effects of BABA. These findings suggested that BABA enhances the cold tolerance of tobacco and is closely related to the state of Ca2+ signaling.

3.
Plant Physiol Biochem ; 153: 119-130, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32498010

RESUMO

Chloride (Cl-) is a micronutrient and a beneficial ion for plant growth, but excess Cl- easily leads to Cl- salinity. As a species sensitive to Cl-, tobacco experiences serious damage when encountering excessive Cl-. However, the molecular mechanism by which excess Cl- delays plant growth and development remain largely unknown. In this study, physiological, biochemical and genetic responses were determined in tobacco plants exposed to 12 h, 24 h and 48 h of Cl- salinity. Compared with the control, Cl- salinity increased the content of Cl- and decreased the relative water content (RWC) in tobacco, which severely limited the photosynthetic capacity and reduced photosynthetic products, resulting in decreased levels of auxin (IAA) and gibberellin (GA3). In addition, tobacco increased the content of starch, total phenol and increased phenylalanine ammonia-lyase (PAL) activity in response to Cl- salinity. Multi-omics results revealed that a total of 15,445 genes and 1983 proteins were differentially abundant in response to Cl- salinity. Two metabolic pathways, phenylalanine metabolism and starch and sucrose metabolism, were specifically enriched in the transcriptomic and proteomic data, respectively. In addition, our conjoint analysis of RNA-Seq and proteomics data revealed that 734 differentially abundant genes/proteins were enriched mainly in plant hormone signal transduction, photosynthesis and photosynthesis-antenna protein pathways. Our work presented here not only provides new insights into the molecular response of tobacco to Cl- salinity but also offers important guidance for the improvement of Cl- sensitive crops.


Assuntos
Cloretos/fisiologia , Nicotiana/fisiologia , Fotossíntese , Reguladores de Crescimento de Plantas/biossíntese , Salinidade , Transdução de Sinais , Folhas de Planta , Proteômica , Estresse Fisiológico
4.
Infect Dis Poverty ; 5: 27, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-27025584

RESUMO

BACKGROUND: Hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) is a potentially life-threatening infectious disease that commonly occurs in children. Diagnosis of HFMD caused by EV71 largely depends on clinical manifestations and rare serological biomarkers used to identify children suffering from HFMD. Serum cholinesterase (SChE) activity has frequently been reported as a potential biomarker for solid central nervous system tumors, chronic heart failure, and liver cirrhosis. However, its potential value in the diagnosis of neurotropic virus infections, such as HFMD caused by EV71, remains to be determined. FINDINGS: In our study, 220 children hospitalized with HFMD caused by EV71, 34 inpatients infected with coxsackievirus A16 (CVA16), and 43 undefined enterovirus-infected HFMD inpatients were recruited at the Anhui Provincial Children's Hospital between January 2011 and December 2012. SChE activity was measured. The non-parametric Mann-Whitney U test showed that SChE activity in children diagnosed with HFMD caused by EV71 was significantly higher than in healthy controls (p < 0.001), as well as in children with upper respiratory tract infections (p = 0.011), bronchopneumonia (p < 0.001), septicemia (p < 0.001), amygdalitis (p < 0.001), and appendicitis (p < 0.001). In addition, higher SChE activity was observed in male inpatients with HFMD caused by EV71 (47.7 % positivity) compared to female inpatients (26.1 % positivity) (chi-square test, p = 0.002). In our study, no significant differences in SChE levels were observed among different ages (up to 120 months) (r = -0.112, p > 0.05). An important finding was that SChE activity declined in the recovery phase of HFMD caused by EV71 compared to the acute phase (p < 0.001). CONCLUSIONS: Elevated SChE activity was observed in patients with severe HFMD caused by EV71. Therefore, SChE might be a potential assistant biomarker for the diagnosis of HFMD caused by EV71 in children.


Assuntos
Colinesterases/sangue , Enterovirus Humano A/fisiologia , Doença de Mão, Pé e Boca/enzimologia , Biomarcadores/sangue , Pré-Escolar , China , Feminino , Doença de Mão, Pé e Boca/sangue , Doença de Mão, Pé e Boca/diagnóstico , Humanos , Lactente , Masculino
5.
Ying Yong Sheng Tai Xue Bao ; 26(7): 2091-8, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26710637

RESUMO

Based on the daily meteorological data of 124 agricultural meteorological sites during 1977-2010 in Yunnan Province, using recommended Penman-Monteith formula by FAO, water requirement and irrigation requirement index in the growth period of flue-cured tobacco were calculated to analyze their spatial and temporal characteristics and change patterns. The results showed that water requirements of flue-cured tobacco in root extending, vigorous, mature periods and field growth period during 1977-2010 were 76.73-174.73, 247.50-386.64, 180.28-258.14 and 528.18-764.08 mm, respectively, and the water requirement of vigorous period was the highest. The average irrigation demand index of each period was -0.02, 0.38, 0.17 and 0.26, respectively. Effective precipitation could meet the demand of flue-cured tobacco in root extending period. Water requirement of flue-cured tobacco in Yunnan Province decreased annually, and the rates of water requirement under the climate change trend in the four periods abovementioned were -12. 42, -21.46, -7.17 and -47.15 mm . (10 a)-1, respectively. The smallest irrigation demand index was observed in Dehong, and the largest in Diqing. The irrigation demand indexes of Dehong, Xishuangbanna and Puer regions were negative in flue-cured tobacco field growth period. The reference crop evapotranspiration, water requirement and effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of latitude. The effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of altitude.


Assuntos
Irrigação Agrícola , Nicotiana/fisiologia , Água/fisiologia , Altitude , China , Mudança Climática , Raízes de Plantas/crescimento & desenvolvimento , Análise Espaço-Temporal
6.
Asian Pac J Cancer Prev ; 13(5): 2349-54, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22901221

RESUMO

OBJECTIVE: Individual studies of the associations between P53 codon 72 polymorphism (rs1042522) and bladder cancer susceptibility have shown inconclusive results. To derive a more precise estimation of the relationship, we performed this systemic review and meta-analysis based on 15 publications. METHODS: We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. RESULTS: We found that there was no association between P53 codon 72 polymorphism and bladder cancer risk in the comparisons of Pro/ Pro vs Arg/Arg; Pro/Arg vs. Arg/Arg; Pro/Pro plus Pro/Arg vs. Arg/Arg; Arg/Arg vs. Pro/Arg plus Arg/Arg (OR=1.06 95%CI 0.81-1.39; OR=1.06 95%CI 0.83-1.36; OR=0.98 95%CI 0.78-1.23; OR=1.06 95%CI 0.84-1.32). However, a significantly increased risk of bladder cancer was found among Asians in the homozygote comparison (Pro/Pro vs. Arg/Arg, OR=1.36 95%CI 1.05-1.75, P=0.790 for heterogeneity) and the dominant model (Arg/Pro plus Pro/Pro vs. Arg/Arg, OR=1.26 95%CI 1.05-1.52, P=0.564 for heterogeneity). In contrast, no evidence of an association between bladder cancer risk and P53 genotype was observed among Caucasian population in any genetic model. When stratifying for the stage of bladder, no statistical association were found (Pro/Pro vs. Arg/Arg, OR=0.45 95%CI 0.17-1.21; Pro/Arg vs. Arg/Arg, OR=0.60 95%CI 0.28-1.27; Dominant model, OR=0.56 95%CI 0.26-1.20; Recessive model, OR=0.62 95%CI 0.35-1.08) between P53 codon 72 polymorphism and bladder cancer in all comparisons. CONCLUSIONS: Despite the limitations, the results of the present meta-analysis suggest that, in the P53 codon 72, Pro/Pro type and dominant mode might increase the susceptibility to bladder cancer in Asians; and there are no association between genotype distribution and the stage of bladder cancer.


Assuntos
Povo Asiático/genética , Polimorfismo Genético/genética , Proteína Supressora de Tumor p53/genética , Neoplasias da Bexiga Urinária/etiologia , População Branca/genética , Estudos de Casos e Controles , Humanos , Prognóstico , Fatores de Risco , Neoplasias da Bexiga Urinária/etnologia
7.
Zhonghua Nan Ke Xue ; 14(8): 680-4, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18817337

RESUMO

OBJECTIVE: To identify and analyze the differential expression of ubiquitin C-terminal hydrolase L-1 (UCHL1) in the testis of rat offspring after maternal exposure to di-n-butyl phthalate (DBP). METHODS: Forty pregnant rats were randomly divided into two groups and given DBP by gastric intubation at the dose of 800 mg/(kg x d) or none from the 14-18th day of pregnancy. Testes were harvested from the fetal and neonatal rats of the normal and exposed groups respectively at GD19 and PND22. The expression of UCHL1 was detected and analyzed by Western blot and immunohistochemistry. RESULTS: The UCHL1 expression was 50% lower in the DBP-exposed group than in the normal controls on GD19 (P < 0.01), but showed no significant difference between the two groups on PND22 (P > 0.05). UCHL1 was mainly located in the cytoplasm and nuclei of spermatogonia, primary spermatocytes and sub-primary spermatocytes in the developmental phase of the testis. CONCLUSION: Exposure in utero to DBP affects the UCHL1 expression in testicular spermatogenic cells, disturbs the balance of the ubiquitin-proteasome system and consequently causes maldevelopment of the testis with thinner seminiferous tubules and reduced count of spermatogenic cells.


Assuntos
Dibutilftalato/toxicidade , Testículo/efeitos dos fármacos , Ubiquitina Tiolesterase/biossíntese , Animais , Animais Recém-Nascidos , Feminino , Imuno-Histoquímica , Masculino , Exposição Materna , Gravidez , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Testículo/embriologia , Testículo/metabolismo
8.
Ying Yong Sheng Tai Xue Bao ; 18(11): 2507-11, 2007 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-18260456

RESUMO

Through field survey and laboratory analysis, this paper studied the distribution characters and interrelationships of sulfur in flue-cured tobacco leaf and available sulfur in soil in Hunan tobacco-growing areas of China. The results indicated that in Hunan tobacco-growing areas, the sulfur content in flue-cured tobacco leaf was relatively high as compared with other tobacco-growing areas in China, which ranged from 0.34% to 1.49%, with the mean of (0.81 +/- 0.26)%. 39.29% of the leaf samples had a sulfur content of < 0.70%, and the sulfur content in different grades of flue-cured tobacco leaves was B2F > C3F > X2F. The available sulfur content in soil was rich, which ranged from 2.20 to 217.60 mg x kg(-1), with the mean of (37.16 +/- 27.59) mg x kg(-1). Among the soil samples collected, 22.58% of them were considered as lack of sulfur ( < or =16.0 mg x kg(-1)), 26.08% had an available sulfur content exceeding 50.0 mg x kg(-1), and 51.34% could satisfy the sulfur demand of high quality tobacco. The available sulfur content in different types of soil was in the order of duck feces mud > yellow mud field > red yellow mud > blue mud field > sand mud field > yellow ash soil > yellow soil. There was a very significant positive correlation between the contents of sulfur in flue-cured tobacco leaf and available sulfur in soil (r = 0.469, P < 0.01).


Assuntos
Nicotiana/química , Folhas de Planta/química , Solo/análise , Enxofre/análise , China , Ecossistema , Folhas de Planta/crescimento & desenvolvimento , Nicotiana/crescimento & desenvolvimento
9.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 25(3): 259-62, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15842152

RESUMO

The clinical thinking modes of "integrative disease and Syndrome" and "integrative macroscopical Syndrome-differentiation and microscopical Syndrome-differentiation" formed in the past half century were merely the primary train of thought and methodology of integrative traditional Chinese and Western medicine. In order to develop them to a higher level, stress should be put on the unity and holism of disordered organism and unity of function, structure and metabolism. It has long been ignored that a parallel and correlated relationship exists between the TCM Syndrome and pathological process of Western medicine, which is a common, set-formed and regular pathophysiological changes with certain development phase, presented in various diseases. Both have common features as that the same pathological process can be seen in different diseases and several pathological progresses can present in one disease, the same Syndrome also can be seen in different diseases and several Syndromes can present in a disease. Moreover, they have the compatible connotation and denotation. The author deduced that pathophysiological basis of main Syndrome is indeed the basic pathological process. Essence of Syndrome is the related pathological processes including abnormal changes in function, metabolism and morphological structure.


Assuntos
Medicina Clínica/métodos , Medicina Tradicional Chinesa/métodos , Pesquisa Biomédica/métodos , Quimioterapia Combinada , Saúde Holística , Humanos , Patologia Clínica/métodos
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